Stoker construction



Jan. 1, 1935. R. BEERS STOKER CONSTRUCTION Filed April 27, 1931 2 Sheets-Sheet l I fioyc a 4 g rs ATTORNEYS Jan. 1, 1935.

R; L. BEERS 1,986,318

STOKER CONSTRUCTI ON Filed April 27, 1931 2 Sheets-Sheet 2 INVENTOR Ra:3 Baa- ATTO RNEYS Patented Jam-1, '19 35 v UNITED STATES PATENrjoFF caSTOKER CONSTRUCTION Royce L. Beers, Detroit, Mich assignor to DetroitStoker Company, Detroit, Mich a corporation of Michigan ApplicationApril 27, 1931, erial No. 533,341 8 Claims. (CL 110-44) This inventionrelates generally to stokers and ing a restricted throat 14communicating with refers more particularly to improved means for a ramcasing 15 adjacent the entrance to the controlling the operation ofstokers. retort. As is usually the case in constructions of Theinvention finds particular utility when the above type, the fuel fromthe hopper is transused in connection with mechanical stokers of ferredto the retort by means of aram 16 mount- 5 the type embodying areciprocable ra n. and ed for reciprocation in the ram casing andacmechanism for intermittently actuating the ram tuated by a crank shaft1'7 having a crank 18 to transfer fuel from a hopper into a retort inconnected to the ram by means of a suitable pitaccordance withvariations in the supply of fuel man or connecting rod 19. The foregoingconin the latter. In stokers of the foregoing type struction is sodesigned that when the ram 16 10 it is particularly desirable andadvantageous-t0 is at the limit of its power stroke, it assumes arrestthe ram when the latter is in the throat a position across the throat 14of the hopper of the fuel hopper so as to closecommunication so as toclose communication between the latter between the latter and retort andthereby preand retort. The ram is shown in the aforesaid vent the firein the retort from creeping back position in Figure land the advantagederived into the hopper. Accordingly, it is one of-the by reason of thisconstruction will be more fully principal objects of this invention toprovide conhereinafter described.

rol means for the ram actuating mechanism The crank shaft 17 in thepresent instance is which, in addition to effecting the desiredinterdriven by a constant speed electric motor 20 pref- 20 mittentoperation of the rain, also insur s arerably of the multiphase typeandconnected to a 20 resting the ram in the aforesaid position. sourceof electric energy through a clapper switch Another object of thisinvention is to provide 21. The clapper switch 21 is preferably of thean arrangement of the foregoing type wherein magnetically operable typeand like the motor 20 arresting the ram in the throat of the hopper ispreferably of conventional design.

s insured pe ve of the p in in t e cycle For controlling the operationof the switch 21 25 of Operation of t e ram at which the timin tothereby regulate the operation of the ram 16,

control means functions to discontinue further the circuit 22 isprovided. As shown in Figure 2,

reciprocation of the ram. this circuit is connected to the source ofelectrical A further object of this invention is to provide energy inadvance of the clapper switch 21 and '30 a construction of the typespecified so designed supplies current to a solenoid 23 and an autothatarresting of the ram in the throat of the matic adjustable time switch24. The solenoid 23 hopper is efiected at the end of the power stroke isconnected in series with the circuit 22 and of the ram or, in otherwords, when the crank serves to magnetically hold the clapper switch 21for reciprocating the ram is at dead center. The in its operativeposition wherein current is supabove construction is advantageous sinceit replied to the motor 20. The time switch 24 is of (111058 thestarting 103d 011 e prime mover for conventional design and ispreferably of the motor actuating the crank to a operated adjustabletypecomprising a synchro- The foregoing as well as other objectswill be nousmotor 25 and a switch 26. The motor 25 made more apparent as thisdescriptionproceeds, is connected in parallel with the main circuit or40 especially when considered in connection with source of electricalenergy in advance of the clap-' 40 the accompanying drawings, wherein:per switch 21 and independent of the circuit 22 Fi u e 1 is af a e e yside cn l view so as to continuously operate. The motor 25 b y inSection h wi n yp 0! Stoker i serves to actuate the adjustable timecontrolled ,which my improved control means may be used; mechanism (notshown) which in turn functions igure 2 is a diagrammatic view of thesystem to periodically actuate the switch 24. The above 45 employed forcontrolling the stoker shown in mechanism is not shown hereinsince it ispart of Figure 1; the standard equipment of conventional adJust- Figure3 is an enlarged fragmentary end eleable time switches. The switch 24,diagrammatic vational view of a portion of the stoker actuating callyshown in Figure 2,is preferably of the single mechanism. a T pole typeand is connected in series with the cir- 50 Generally described, thereis fragmentarily ilcult 22 for opening and closing the same.

lustrated in Figure 1 a furnace 10 having a re- It is to be understoodfrom the previous dc,- tort 11 and a stoker 12 for supplying fuel to therescription that the time switch 24 in the present tort. The stoker 12is located exteriorly of instance functions to automatically start andstop 65 the furnace and comprises a fuel hopper 13 hav the ram atpredetermined intervals depending upon the particular adjustment thereofwhich in turn depends upon the particular installation and the rate atwhich fuel is consumed. The manner in which the time switch 24 functionsto periodically actuate the ram is believed obvious from the above.However, assuming that the ram is operating and that the adjusted timeinterval is up, the switch 24 automatically opens the circuit 22 andsince both the latter and solenoid are in series in the circuit 22, itnecessarily follows that the solenoid is ole-energized permitting theclapper switch 21 to open. Opening of the switch 21 disconnects the ramactuating motor 20 from the source of electrical energy and as aconsequence; discontinues further operation of the ram. When the periodof rest of the ram has elapsed, the switch 24 automatically closes thecircuit 22 permitting the flow of current from the source of circuit 22to energize the soleno1d 23 and thereby close the clapper switch toconnect the ram actuating motor 20 with the source of electrical energy.In connection with the foregoing, it is to be noted that if desired, athree way switch 27 may be placed in the circuit 22 for shunting out theautomatic time switch and permitting the system to be actuated manually.

As shown in Figure 2, when the switch 27 is in engagement with thecontact 28, the control is automatic as previously described, but whenthe switch engages the contact 29, it forms a shunt across the circuitcutting out the automatic switch 24. When, on the other hand, the switch27 is moved to a position intermediate the two aforesaid positions, thecircuit is broken and operation of the ram discontinued.

While it will be apparent that the above arrangement functionsefiiciently for automatically and periodically actuating the ram,nevertheless,

is arrested as soon as the time interval controlled by the automatictime switch has expired irrespective of the position of the ram in thestoker. In other words, with the construction siderable starting load isplacedon the motor for actuating the same and the fire in the retort isfree to creep out into the hopper or ram casing. In order to overcomethe above objections, I provide means for insuring arresting of the ramarranged in parallel in the circuit 22 between the solenoid 23 switch27, depending upon which is in use, has been previously operated to openthe circuit. The primary function of the switch 30 as will be apparentfrom Figure 2 is to maintain the solenoid 23 energized closed until theram reaches the end of its power stroke across the throat of the hopper,in the event either the switch 27 or switch 24 depending upon which isused is opened at any other in the cycle of operation other words,before the circuit to the ram actuating motor can be broken, the switch30 and either of the switches 27 and 24, depending upon which is used,must be opened and sincevthe switch 30 is controlled by the ram, itnecessarily follows that arresting of the latter in a predeterminedposition within the stoker is insured.

Thus, from the foregoing it will be apparent that I have provided meansfor automatically and periodically actuating the ram of a stoker,together with means controlled by the ram for arresting the same in apredetermined pwition within the stoker irrespective of the positionthereof at the time the means aforesaid functions to discontinueoperation thereof.

What I claim as my invention is:

1. In a stoker having a fuel hopper, a ram casing having an opening forreceiving fuel from the hopper, a retort for receiving fuel from thecasing, a reciprocating ram in the casing controlling communicationbetween the hopper and retort, said ram being operable when at theforward limit of its stroke to close all communication between thehopper and retort, and actuating mechanism for the ram including arotary shaft, an electric motor for driving said shaft, and a pitmanoperatively connected to the shaft and ram, a switch controlling themotor, and means fo controlling the operation of said switch including asecond switch, and means ward limit of its stroke to cut off allcommunication between the hopper and retort, including a switch forshunting the second switch, said being normally closed and having anoperating member, and means movable with the pitman and operable whenthe ram reaches the forward limit of its stroke to actuate saidoperating meiiber to open the shunting switch, the construction andarrangement of the switches aforesaid being such that opening andclosing the shunting switch has. no effect upon the operation of the ramunless the second switch aforesaid is open. I

2. In a stoker having a fuel hopper, a ram casing having an opening forreceiving fuel from 1: hopper, a retort for receiving fuel from thecasing, a reciprocating ram in the casing conswitch including anautomatic time switch, a manually operable switch for switch, and meansfor arresting the ram when it reaches the forward limit of its strokeirrespective of the position thereof at the time either the time switchor the manually operable switch depending upon which is for holding theswitch 21 of the ram. In

shunting the time used is opened, said retort, said ram being operablewhen at the forward limit of its stroke to closeall communicationbetween the hopper and retort, and actuating mechanism for the ramincluding a rotary shaft, an electric motor for driving said shaft, anda pitman operatively connected to the shaft and is open.

casing, a reciprocating ram, 9. switch controlling the motor, and meansfor controlling the operation of said switch including an automatic timeswitch, and means for arresting the ram when it reaches the forwardlimit of its stroke to cut off all communication between the hopper andretort, including a switch for shunting the time switch, said shuntingswitch being normally closed and having an'opcrating member, and meansmovable with the pitman and operable when the ram reaches the forwardlimit of its ing member to open said shunting switch, the constructionand arrangement of the switches aforesaid being such that opening andclosing the'shunting switch has no effect upon the operation of the ramunless the time switch is open.

4. In a stoker having a fuel hopper, a ram casing having an opening forreceiving fuel from the hopper, a retort for receiving fuel from the ramin the casing controlling communication between the hopper and retort,said ram being operable when at the forward limit of its stroke to closeall communication between the hopper and retort, and actuatin mechanismfor the ram including a rotary shaft, an electric motor for driving saidshaft, and a pitman operatively connected to the shaft and ram, a switchcontrolling the motor, and means for controlling the operation of saidswitch including an automatic time switch, a manually operable switchfor shunting the time switch, and means for arresting the ram when itreaches the forward limit of its stroke to cut off all communicationbetween the h pper and retort, including a trip movable with the pitmanand a switch for shunting both the manually operable and time switches,said last mentioned switch being opened by the trip when the ram reachestheforward limit of its stroke and automatically closed when free of thetrip, the construction and arrangement of the switches aforesaid beingsuch that opening and closing the last mentioned switch has no effectupon the operation of the ram unless either the time switch or themanual- 1y operable switch depending upon which is used 5. In a stokerhaving a fuel hopper, a ram casing having an opening for receiving fuelfrom the hopper, a retort for receiving fuel from the casing, areciprocating ram in the casing controlling communication between thehopper and retort, said ram being operable when at the forward limit ofits stroke to close all communication between the hopper and retort, andactuating mechanism for the ram including a rotary shaft, an electricmotor for driving said shaft, and a pitman pperatively connected to theshaft and ram, 2. switch controlling the motor, and means forcontrolling the operation of said switch including a second switch, andmeans for arresting the ram when it reaches the forward limit of itsstroke to cut off all communication bestroke to actuate said operattweenthe hopper and retort, including a switch for shunting the secondswitch, said shunting switch being under the control of the pitman so asto be opened when the ram reaches the forward limit of its stroke andbeing automatically closed, the construction and arrangement of theswitches aforesaid being such that opening and closing the lastmentioned switch has no effect upon the operation of the ram switchaforesaid is open.

6. In a stoker having a fuel hopper, a ram casing having an opening forreceiving fuel from the hopper, a retort for receiving fuel from thecasing, a reciprocating ram in the casing controlling communicationbetween the hopper and retort, said ram being operable when at theforward limit of its stroke'to, close all communication between thehopper and retort, and actuating mechanism for the ram including arotary shaft, an electric motor for driving said shaft, and a pitmanoperatively connected to the shaft and ram, a switch controlling themotor, and means for controlling the operation of said switch includingan automatic time switch, a manually operable switch for shunting outthe time switch, and means for arresting the .ram when it reaches theforward limit of its stroke to cut off all communication between thehopper and retort, including a switch for shunting both the manuallyoperable switch and time switch, said second named shunting switch beingnormally closed and having an operating member, and means movable withthe pitman and operable when the ram reaches the forward limit of itsstroke to actuate said operating member to open said second namedshunting switch, the construction and arrangement of the switchesaforesaid being such that opening and closing the second named shuntingswitch has no effect upon the bperation of the ram unless either thetime switch or the manually operable switch depending upon which is usedis open.

'1. In a stoker having a fuel hopper, a ram casing having an opening forreceiving fuel from the hopper, a retort for receiving fuel from thecasing, a reciprocating rain in the casing controlling communicationbetween the hopper and retort, said ram being operable when at theforward limit of its stroke to close all communication between thehopper and retort, and actuating mechanism for the ram including arotary shaft, an electric motor for driving said shaft, and a pitmanoperatively connected to the shaft and ram, a switch controlling themotor, and means for controlling the operation of said switch includingan automatic time switch, a. manually operable switch for shunting thetime switch, and a switch for shunting both the manually operable switchand time switch, said second named shunting switch being under thecontrol of the pitman so as to be opened when the ram reaches theforward limit of its stroke and being automatically closed, theconstruction and arrangement of the switches being such that opening andclosing the second named shunting switch has no effect upon theoperation 'c-f the ram unless either the time switch or the for the ramincluding a. rotary shaft, an electric motor for driving said shaft, anda. pitman operatively connected to the shaft and ram, a switchcontrolling the motor, and means for controlling the operation of saidswitch including an automatic time switch, a manually operable switchfor shunting the time switch, and means for arresting the ram when itreaches the forward limit of its stroke to out 01? all communicationbetween the hopper and retort including a switch for shunting both thetime and manually operable switches, said second named shunting switchbeing under the control of the pitman so as to be opened thereby whenthe ram reaches the forward limit of its stroke and being automaticallyclosed, the construction and arrangement of the switches aforesaid beingsuch that opening and closing the second named shunting switch has noeifect upon the operation of the ram unless either the time switch-orthe manually operable switch depending upon which is used is open. l

' ROYCE L. BEERS.

